Pardon me but that's not the answer because "did they pull out of the game to gain card exp?" is not the question. People pull out of games when they know they have a bad draw or when the game is already lost, leaving people who don't pull to suffer manipulated odds.
Sure ELO mode ban cards that are too powerful, but does this new measure do anything to ELO players who don't finish their games? Do they need the card exp or 4 Clintz?
The bandwidth usage of this game is minimal, and anyone today can afford a good connection. There's nothing wrong with giving a straight loss to anyone who doesn't finish a game for any reason.
The problem that I'm seeing with Timeouts is often with people who've already lost that are trying to help their friends win. The two main tactics are to, a) Timeout at the beginning of matches, or b) just not answer challenges because they're idle (or pretending to be). Now B is harder to combat, but adding an idle time next to people's names could help immensely in combatting B. I mean even I have had to leave my computer for a minute or two.
The final tactic I've seen (and I see this one a lot more than timeouts these days) is slow play. People taking 4-5 minutes to make a move. Where when it's not tournament play I see these same people able to make moves quite quickly. The best way to combat this is to put a move timer on, give it say, 2 min (which if you've not made a move the computer will randomly select one of your remaining characters for you). If people are planning their strategies during their opponent's turn like they should be (It's what I do), or can't plan an opening move in 2 minutes, then they need help anyway.
This isn't a difficult game, and certainly not difficult enough that quick decisions can't be made. I mean you have a basic idea what your deck's going to do because you made it. It doesn't take long to analyze what you've got and what your opponent has and to make an opening move. These are the biggest problems I see and readily identify without speculation as to what's going on on the other side of the computer screen.